G. Install Attic Insulation Shield
Warning! Risk of Fire! You MUST install an attic insu- lation shield when there is any possibility of insulation or other combustible material coming into contact with the chimney.
•Do NOT pack insulation between the chimney and the attic insulation shield.
•Failure to keep insulation and other materials away from chimney pipe could cause fire.
•Do NOT offset chimney inside insulation shield.
Installation of a ceiling firestop is required
•Refer to Figures 8.8 - 8.10.
•Roll the shield (around the chimney if already installed) until you have a 3 in. (76 mm) overlap and the three holes on each side match up (large holes on top).
•Insert three screws into the matching holes to form a tube.
•Bend three tabs on the bottom of the tube inward to 90° to maintain chimney air space (refer to Figure 8.8).
•Rest the insulation shield on the ceiling firestop below.
•Bend the three short tabs at the top of the shield inward to 90° to maintain the 2 in. (51 mm) air space from the chimney.
•Bend the remaining top tabs to just meet the pipe.
If you wish to make a custom shield or barrier, follow these guidelines:
•Metal is preferred, although any material stiff enough to hold back the insulation can be used.
Warning! Risk of Fire! Use of cardboard or other materials that can deflect under humidity or other envi- ronmental conditions is not recommended.
•The shield or barrier must be tall enough to extend above the insulation and prevent
•Maintain specified air spaces around chimney.
•Check instructions and local codes for further details.
H. Secure the Chimney
When offsets and returns are joined to straight pipe sec- tions, they must be locked into position with the screws pro- vided* (outer only), using the predrilled holes. To prevent gravity from pulling the chimney sections apart, the returns and the chimney stabilizers have hanger straps for secur- ing these parts to joists or rafters. See Figure 8.11 on page 48.
*Use #6 or #8 sheet metal screw, or larger, no longer than 1/2 in. (13mm).
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| Bend remaining tabs |
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| to rest against pipe to |
Bend |
| inward | prevent insulation | |
90° |
| from falling in. | ||
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| Insert three |
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| screws |
| 3 in. (76 mm) | |
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| overlap |
Figure 8.8 Prepare Attic Insulation Shield | ||
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| Tabs bent in to |
| Pipe | rest against pipe |
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| Attic Insulation Shield |
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| 6 Tabs bent | diameter |
| in 90° | Ceiling Firestop |
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Insulation | Pipe | Insulation |
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(267 mm) |
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Figure 8.9 Install Attic Insulation Shield (firestop above ceiling)
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| Tabs bent in to | |
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| rest against pipe | |
| Pipe |
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| Attic Insulation Shield | |
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| diameter | |
| 6 Tabs bent |
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| in 90° |
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Insulation |
| Insulation | |
Pipe | Ceiling Firestop | ||
(267 mm) | |||
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Figure 8.10 Install Attic Insulation Shield (firestop below ceiling)
4/12 | Heatilator • Constitution EPA Fireplace • | Page 47 |